Power control system for electrical apparatus

Abstract

A power control system enables an electrical apparatus to intermittently operate at power levels which exceed an available facility power. The power control system draws a sufficiently high current from a power source (e.g., mains supply) to supply power to components of the apparatus that generate a continuous below-threshold load, while at the same time, supplying a charge current for a battery module. The power control system can operate to use the battery module to supply power to components of the apparatus that draw excess power when the electrical apparatus operates at an above-threshold power level.

What is claimed is: 
     
         1 . A power control system comprising:
 a supply circuit to:
 draw current from an alternating current source at a level that is below a predetermined threshold; 
 use a proportion of the drawn current to continuously power an electrical apparatus at below the predetermined threshold; and 
   a power controller to supply a charge current to the rechargeable battery module using a remainder of the proportion of the drawn current that powers the electrical apparatus, and to supply power to the electrical apparatus from the rechargeable battery module independent of the drawn current from the alternating current source, the supplied power of the rechargeable battery module meeting a power requirement of the electrical apparatus that would otherwise exceed the predetermined threshold.   
     
     
         2 . The power control system of  claim 1 , wherein the power controller modulates the charge current based on a power requirement of the electrical apparatus when the electrical apparatus operates at below the predetermined threshold. 
     
     
         3 . The power control system of  claim 1 , wherein the power controller independently supplies power from the rechargeable battery module to the electrical apparatus at a level that exceeds the predetermined threshold while the supply circuit uses the proportion of the drawn current to continuously power the electrical apparatus at below the predetermined threshold. 
     
     
         4 . The power control system of  claim 1  wherein the power controller independently supplies power from the rechargeable battery module to the electrical apparatus at a level that exceeds the predetermined threshold while the supply circuit supplies the charge current for the battery using the remainder of the drawn current. 
     
     
         5 . The power control system of  claim 1 , wherein the power controller modulates the drawn current in supplying the charge current, so that the drawn current remains within a constant range, while the proportion of the drawn current powers a varying load of the electrical apparatus. 
     
     
         6 . An electrical apparatus comprising:
 a supply circuit to:
 draw current from an alternating current source at a level that is below a predetermined threshold; 
 use a proportion of the drawn current to continuously power an electrical apparatus at below the predetermined threshold; and 
   a power controller to supply a charge current to the rechargeable battery module using a remainder of the proportion of the drawn current that powers the electrical apparatus, and to supply power to the electrical apparatus from the rechargeable battery module independent of the drawn current from the alternating current source, the supplied power of the rechargeable battery module meeting a power requirement of the electrical apparatus that would otherwise exceed the predetermined threshold.   
     
     
         7 . The electrical apparatus of  claim 6 , wherein the first load of the electrical apparatus is provided by a first set of components while the electrical apparatus is operating under a low power mode, and wherein the above-threshold load of the electrical apparatus is provided by a second set of components of the electrical apparatus while the electrical apparatus is operating under a high-power mode. 
     
     
         8 . The electrical apparatus of  claim 6 , wherein the above-threshold load is intermittent over a duration of time during which the current from the alternating source is being drawn. 
     
     
         9 . The electrical apparatus of  claim 8 , wherein the electrical apparatus is an additive printing apparatus, and wherein the above-threshold load is triggered when the electrical apparatus initiates performance of a print job. 
     
     
         10 . The electrical apparatus of  claim 8 , wherein during the portion of the first time interval, the supply circuit supplies power to the first load independently of the power controller supplying power to the above-threshold load at the level that exceeds the predetermined level. 
     
     
         11 . The electrical apparatus of  claim 8 , wherein the first load fluctuates during the first time interval, and wherein the supply circuit modulates the proportion and the remainder of the drawn current in response to the first load fluctuating. 
     
     
         12 . The electrical apparatus of  claim 8 , wherein the above-threshold load fluctuates during the second time interval, and wherein the power controller controls an output of the battery to match the second fluctuating load. 
     
     
         13 . The electrical apparatus of  claim 8 , wherein the power controller modulates the drawn current in supplying the charge current, so that the drawn current remains within a constant range, while the proportion of the drawn current powers a varying load of the electrical apparatus. 
     
     
         14 . A method for controlling power to an electrical apparatus, the method comprising:
 drawing current from an alternating current source at a level that is below a predetermined threshold;
 using a proportion of the drawn current to continuously power an electrical apparatus at below the predetermined threshold, while supplying a charge current for the battery using a remainder of the drawn current; and 
 independently supplying power from the battery to the electrical apparatus at a level that exceeds the predetermined threshold during intervals in which a power requirement of the electrical apparatus exceeds the predetermined threshold. 
   
     
     
         15 . The method of  claim 14 , further comprising supplying the charge current by modulating the drawn current, so that the drawn current remains within a constant range, while the proportion of the drawn current powers a varying load of the electrical apparatus.